Rabies kills an estimated 55,000 people each year, mostly in Asia and Africa. This week marked the fourth annual World Rabies Day, a global effort to increase rabies knowledge and prevention.

The U.S. Centers for Disease Control and Prevention (CDC) released a study: "Rabies surveillance in the United States during 2009," to coincide with the event. According to the study, in 2009, 49 states and Puerto Rico reported 6,690 rabid animals and four human rabies cases. The number was a 2.2 percent decrease from the 6,841 rabid animals and 2 human cases reported in 2008. Approximately 92% of reported rabid animals were wildlife, the CDC says. Raccoons accounted for the largest percentage of rabid animals (34.8 percent), followed by bats, skunks, foxes, cats, dogs and cattle.

In the same study, the CDC reported that although no human rabies cases had been reported in the first seven months of 2010, there was an increase in rabid New York raccoons.

"A substantial increase in the number of rabid raccoons reported from New York City occurred during the first half of 2010 because of an epizootic in raccoons in Central Park," the report says. "At least 116 rabid raccoons were reported from Manhattan as of June. A trap, vaccinate, and release program was initiated inFebruary to attempt to control this epizootic."

The World Rabies Day initiative is a joint effort between the CDC and the Alliance for Rabies Control, a UK charity. The organization aims to bring together relevant partners in an effort to address rabies prevention and control.